Changzhou Institute of Technology

Conventional metasurfaces are inherently frequency-selective, limiting wavefront control to a single operating frequency. Achieving independent manipulation at multiple frequencies remains a significant challenge for expanding the capabilities of integrated optics. Here, we propose and demonstrate an all-silicon metasurface platform that enables arbitrary independent wavefront shaping at two distinct terahertz frequencies. Our design leverages meta-molecules that synergize geometric and propagation phases to decouple the phase profiles for each frequency under a single polarization. This work provides a versatile platform for spatial-domain multiplexing, paving the way for high-capacity communication and multifunctional terahertz photonic devices.

In this paper, we demonstrate β-Ga2O3 solar-blind photodetectors working over 300 °C and investigate the carrier transition mechanism. The (−201) β-Ga2O3 films were grown on sapphire substrates using the carbothermic reduction method and further fabricated into a metal–semiconductor–metal solar-blind photodetector. The solar-blind photodetectors exhibited a low dark current of approximate 10 pA and a high photo-to-dark current ratio (PDCR) of approximately 4419 at a high temperature of 300 °C, thanks to the Schottky barrier that impedes thermally excited carriers from overcoming the barrier to enter the semiconductor conduction. The multiple cycles of the transient response curve of β-Ga2O3 solar-blind photodetectors demonstrated its repeatability and reversibility at high temperatures. Above 300 °C, the dark current displays a sharp increase while the PDCR exhibits a dramatic descent of several orders of magnitude. The reason could be explained by the carrier transition mechanism shifted to the thermionic field emission model at high temperature by analyzing the fitting curve of dark current over 400 °C causing a sharp increase in dark current and degeneration of device performance.

The launch accuracy of micro-spacecraft is crucial to the successful implementation of the active space debris removal mission. Based on ADAMS software, a virtual prototype model of a micro-spacecraft launch platform is established. Considering the influence of uncertain factors such as thrust eccentricity, the Monte Carlo random sampling method is used to simulate and analyze the separation process. Taking the circular probability error as the quantitative evaluation index of the launch accuracy, the influence of the key structural parameters of the separation mechanism on the launch accuracy is studied by the parametric random simulation system. The results show that the guide rail clearance is the key parameter affecting CEP. When the guide clearance is set to 0.2 mm, the slip length is increased to 140 mm, or the step thickness is controlled at 1.3 mm, a lower CEP value can be obtained.

Chirality transfer across hierarchical architectures represents a pivotal and underexplored challenge in the design of functional chiral materials. Through molecular engineering integrating chiral α-terminal groups with electronically tunable azobenzene (Azo) side chains, we demonstrate that in kinetically trapped aggregates of side chain Azo polymers, the dipole moment of the chromophore, modulated by terminal electron-donating (Donor, D) or withdrawing (Acceptor, A) substituents, dictates the absolute inversion of the resulting supramolecular helix. The substituent-dependent dipole reorientation cascades into long-range helical reorganization via π-π and van der Waals cooperativity, ultimately governing whether chirality transfer follows thermodynamic preference, undergoes inversion, or exhibits multiplexed behavior. This electronically driven chirality inversion transcends classical steric models and establishes a transformative framework for designing adaptive chiral materials with programmable handedness, offering promising applications in photonic circuits, enantioselective nanosensors, and bioinspired metamaterials.